Method and machine for the manufacture of metallic frames for inner spring mattresses

ABSTRACT

A round wire or flat wire promoted and having been straightened by the feeding straightening mechanism is measured by the length measuring instrument and shaped into a suitable elliptical or circular shape by a rotating arm with a jaw, is then cut to the desired length by a cutter, its ends being suitably shaped by a shaper prior to or following it and are connected by a connective mechanism with a suitable connective plate in a manner that the material of the means of connection penetrates into the suitable incisions formed by the cutter or the shaper. In the sequel, an arm transports the frame for bending into a suitably arranged bending unit where the frame takes its final shape.

[0001] The present Invention Alteration refers to invention with No960100215 which is dealing with a method and a machine for the manufacture of metallic frames for the Inner Spring Mattresses.

[0002] It is known that metallic frames, which are made of round wire or flat round wire and the ends of which are connected rigidly together with a plate, are necessary for the manufacture of inner spring mattresses for the circumferential support of the springs. The said closed frames have the shape of the mattress under construction.

[0003] The most widely used method of construction of such metallic frames necessitates the use of at least two machines, the design of which is based on a method for the formation of round wire or flat wire, the stages of which follows the following series: feeding and straightening of the round wire or of the flat wire, bending into the final shape of the frame, cut-off, collection and transportation of the open frame manually to a connective machine and finally, connection of the two ends with a metallic clip.

[0004] Alternatively, the connection of the two ends is performed with a small tube instead of the plate or with butt welding.

[0005] The principal drawbacks of the existing technology are: two machines are used: the straightening-bending machine and the connective machine which are independent of each other. For this reason, manual work is necessary for the collection and transportation of the open frame to the connective machine. The worker collects the difficult to handle open frame, which bends easily, transports it to the connective machine, supplies the machine with the said open frame suitably positioned, activates the machine, which connects the two free ends of the open frame with a metallic clip or a small tube or by butt welding in the sequel the worker collects the closed frame and repeats the above procedure for each new frame for construction. It must be emphasized that the manual actions are usually performed by more than one worker for achieving a decent productivity.

[0006] During bending all the sides of the already manufactured frame rotate with respect to one of its corners. As the frame is still open during the bending process, it exhibits a high degree of flexibility. For this reason the speed of rotation of the frame and consequently the speed of the bending is low. The movement of the open frame requires a large space and leads to an horizontal arrangement of machine of large sizes, e.g. for rotating a frame cross section of 2 meters×2 meters with respect to one of its corners, a free circular space of a radius equal to its diagonal is required, i.e. of 2,8 meters. The bending step in an horizontal arrangement after the two ends of frame under construction is free leads to low speeds of feeding of the round wire or flat wire.

[0007] Due to the flexibility and due to the fact that the two ends of the frame are free, the handling performance is especially difficult, both during the collection and during suitable positioning of the two ends in the connective machine. This is the principal reason that until today, the complete automation of the production of open frames for inner spring mattresses has not been possible and for the necessity for manual work by the personnel.

[0008] It is evident that this manufacturing process leads to a waste of time, high labour costs and low productivity.

[0009] The aim of the present invention is to solve the problems described above by offering a method which permits the automated manufacture of metallic frames for inner spring mattresses in a simple and quick manner.

[0010] The objective of the present invention is to offer an arrangement which renders the automation of the manufacture of metallic frames for inner spring mattresses possible, and which is simple in its design, reliable in its operation and easy to use.

[0011] More details of the arrangement according to the Invention 960100215 will be made understood by the description below of a particular application of it. A method of application of the invention is described in the sequel, with references to drawings which explain a particular implementation, are:

[0012] Drawing 1 is a side view and partial longitudinal cut of the machine for the manufacture of metallic frames for inner spring mattresses.

[0013] Drawing 2 is a top view and partial cut.

[0014] Drawing 3 is a cross sectional view.

[0015] Drawing 4 is a side view of the part with the connective mechanism.

[0016] Drawing 5 is a cross sectional cut of the machine.

[0017] Drawing 6 illustrates an example of the connection of the two ends of a metallic frame for inner spring mattresses of round wire of a circular cross section constructed by the machine according to the present invention.

[0018] Drawing 7 illustrates an example of the connection of the two ends of a metallic frame for inner spring mattresses of round wire constructed by the machine according to the present invention.

[0019] Drawing 8 illustrates another implementation of the connection of the two ends of a metallic frame for mattresses fitted with springs made of flat wire, constructed by the machine according to the present invention.

[0020] Drawing 9 illustrates an example of a metallic frame for inner spring mattresses constructed by the machine according to the present invention.

[0021] Drawing 10 illustrates another implementation of a metallic frame for inner spring mattresses constructed by the machine according to the present invention.

[0022] Drawing 11 illustrates another implementation of a metallic frame for mattresses fitted with springs constructed by the machine according to the present invention.

[0023] Drawing 12 illustrates all the stages of the connection of the two ends of the frame in a cross sectional cut of the connective mechanism.

[0024] Drawing 13 is a front view of the connective mechanism.

[0025] Following its straightening, the round wire or the flat wire (1) is fed with the assistance of a rotary mechanism (8), an open elliptical or circular frame is produced with a length equal to the circumference of the frame under construction. Following feeding of the necessary round wire or flat wire (1) the cut-off is performed with simultaneous formation of incisions in the surface of the round wire or flat wire (1) using a cutter (4). Alternatively, the formation of the ends of the round wire or flat wire may be performed by a forming device prior or following the cut-off. The two ends of the circular frame come into contact with the assistance of the rotary mechanism (8) into a connective mechanism (6) where they are rigidly retained appropriate position by tow jaws (22,23) in the. The two ends, being in contact, are wound by the connection plate (14) which comes from a spinning wheel (10), and which is fed by a mechanism with an adjustable step (15) and is then suitably pressed so that the material of the connection plate (14) penetrates into the incisions of the ends of the round wire or flat wire (1). In this manner the strong connection of the two ends of the frame under construction is ensured. The closed frame produced is transported by an arm (13) to the bending unit (9) where it is bent to particular positions and at particular angles so that a frame of a desirable shape is produced. If the frame is made of round wire (1), the said round wire (1) is formed into an ellipse or circle bent across the axis with the smaller inertia torque and then at the bending unit (9) it is bent at the suitable angle, usually at right angles to the plane of the initial elliptical or circle.

[0026] The above mentioned method is implemented, in the machine the description of which follows. The operation of the individual mechanisms is controlled by a microprocessor. The round wire or flat wire (1) is fed and straightened in the feeding-straightening mechanism (2), whereas the fed length of the said round wire or flat wire (1) is measured by the measuring device (3). In the sequel, the material passes through the cutter (4) which is suitably formed so that shaping of the ends of the round wire or flat wire (1) is performed along with the cut-off and is fed through the guide (5) towards the connective mechanism. In the outlet of the said connective mechanism the jaws (7) of the rotary arm (8) is located. The round wire or flat wire (1) is secured by the jaws (7), the rotary arm (8) rotates simultaneously in co-ordination with the feeding-straightening mechanism (2) and transports the jaws (7) to the across side of the connective mechanism (6) without yet being in contact with it, forming an open elliptical or circular frame. After the length of the fed material is equal to the circumference of the frame under construction cut-off and suitable forming of the ends occurs in the cutter (4), whereas the edge of the produced frame and the other edge of the subsequent frame are formed. The round wire or flat wire (1) of the frame produced is then fed by the existing round wire or flat wire (1) of the subsequent frame in the connective mechanism (6) via the guide (5), which consists of two parts: a fixed and a moving one, suitable for free rotation around the pin (17). The feeding stops after the ending of the round wire or flat wire (1) of the frame under production reaches a particular position of the mechanism (6). There, the round wire or flat wire (1) is secured by a jaws (23) so that it remains stationary. The new round wire or flat wire (1) of the subsequent frame moves backwards by a particular length so that it frees the moving one part of the guide (5). Then, the jaws (7) moving along a curve line by the rotary arm (8) brings this second edge of the open fame into contact with the first, which is retained steadily by the jaws (23) at the connective mechanism (6) displacing the part of the guide (5) moving freely around the pin (17). The edge of round wire or flat wire (1) held by the jaws (7) is secured by a second jaws (22) and thus the two ends of the round wire or flat wire (1) are rigidly held and in contact with each other at a suitable position of the connective mechanism (6).

[0027] The connection plate (14) coming from the wheel (10) is fed by the feeding mechanism (15) with an adjustable steady step to the connective mechanism (6) at right angles to the round wire or flat wire (1) of the frame under construction and at a length depending on the circumference of the said round wire or flat wire (1) (Drawing 12A) ; it then intersects at the respective length with the assistance of a fixed (20) and or a moving one cutter (19) which, moving upwards as illustrated in Drawing 12A) and with the assistance of the downwards moving shaper (18) it bends the connective plate (14) around the round wire or flat wire (1) (Drawing 12B). in the sequel, the upper shaper (18) moving upwards frees the connection space, a second shaper (21) comes from the side to the connection area Drawing 12C) moving along an arc, the other shaper (18) moves again downwards pushing the second shaper (21) which then shapes the connective plate (14) so that the two ends of the said plate (14) converge to the plane of the longitudinal symmetry axis of the round wire or flat wire (1) Drawing 12D). In the subsequent phase, the upper shaper (18) moves upwards, the second shaper (21) frees the connection space, moving to the side along an arc, the upper shaper again descends and presses the round wire connection (14) (Drawing 12E) hardly so that the material of the said connective plate (14) penetrates into the incisions of the round wire or of the flat wire (1) of the frame under construction resulting in a strong connection of the ends of the frame as illustrated in drawings 6 and 7. Alternatively, the connection can be performed by hooking the suitably shaped ends as illustrated in the example of Drawing 8 or by butt welding or by glue and suitable plate or small tube. The frame which is now closed is transported by the arm (12) to the bending mechanism (9) located across of the connective mechanism (6). This consists of the feeding-length measurement sheaves (11) and the bending sheaves(12). The closed frame is fed and curved at predetermined positions and angles so that the frame required is produced. In particular, should the material of the frame is round wire (1), the bending mechanism is positioned so that the round wire (1) is curved under a suitable angle, usually at right angles to the plane of the closed elliptical or circular frame at particular angles and predetermined positions. After the closed frame is transported with the assistance of the arm (12) to the bending mechanism (9), the production of the next fame starts in parallel with the bending of the frame under construction and thus productivity of the machine is maximized.

[0028] To the above described method there are a number of disadvantages.

[0029] The cutting and the Grooving of the wire ends is taking place on the same press so required a lot of tool strength and a lot of tools where is taking place. Also, in order to transport the beginning of the wire (Round or Flat) in the connection mechanism (6) the looping arm (8) is used where a gripper (7) is fitted at its end. This configuration requires for the wire to stop at the position where the gripper 7 is located. Then, the activation of the gripper is required in order for the wire to be trapped inside. The gripper's activation is achieved with the use of Hydraulic or Pneumatic Piston which is required to be located along side the looping Arm (8). In addition, the oil of Air Supply tube is required to be rotated as well. On completion of the hand over of the beginning of the wire to the gripper (22) a return activation mechanism of the looping Arm (8) must be initiated in order for the looping Arm (8) to be returned to its original position.

[0030] All these require a very complicated mechanism in order for the method to be materialized.

[0031] Also, the fact that the pressing tool (21) has to form an Arc during its operation in order to come side ways to the pressing Area (12 c) and the one pressing tool (18) requires to be more downwards pushing the second pressing tool (21) which forms the clipping making the possibility of very often breakages of the tools in addition to the fact that if the cutting tool breaks the whole system needs to be changed.

[0032] According to the present invention of the transportation of the beginning of the wire (Round or flat) is achieved by its own movement because it is inserted in a groove (25), which belongs to the guide (24). The groove is covered by a cover (26), Drawing 16. The round or flat wire by entering the position 24 a, Drawing 15 of the guide because of the continuous feeding ends up at the position 24 b where 2 rollers (31) and (32) are engaging it (Drawing 14,15) so its location and stoppage. When the beginning of the wire reaches the cover 26, Drawing 16 by its move frees the groove (25), (Drawing 16 and 16 b) so the wire (Round or Flat) free now can take the required length without restriction.

[0033] With the completion of the required length of the frame the cutting and the grooving of the wire as well as the feeding of the cut length with its beginning of the new frame to the pressing mechanism (16) where the end of the frame is trapped from the gripper (23), (Drawing 13). Then the beginning of the new frame is retracting allowing the rollers (31) and (32) to rotate so feeding the ends to get joined together. Then the gripper (22), Drawing 13 is closing.

[0034] The two wire ends are winding with the clipping material (14) which is getting unwinded continuously by a coil/swift (10) which is advanced from feeding adjustable step mechanism(15).

[0035] The clipping material (14) is suitably pressed so to enter the grooves at the wire ends of the produced frames. When the wire end has been clipped the loop is transported to the bending mechanism (9) through a transportation mechanism (13) where the required frame is produced

[0036] The big advantage of this invention is that the entrance of the wire (Round and flat) at the groove of the guide (24) is moving and arriving without secondary mechanism at a point before its entrance on the clipping mechanism without requiring the initial length measurement stoppage to the gripper to catch it and to start feeding again.

[0037] With this method it is gained time on the production of the frames and all the mechanism is simplified for the catching, transportation and entrance of the beginning at the processing mechanism.

[0038] In addition according to the present invention the pressing tool mechanism (21) which has to form an Arc during its operation in order to come sideways in addition to the auxiliary clipping tools (18,20) (Drawing 12) are all located on to a tool magazine (Drawing 17) which is moving only perpendicular to the wire line with intermediate positions which correspond to the required tool needed to perform a job. Thus the possibility of tool breakages is minimized because the action of the operating clipping tools is only perpendicular and not in the form of an Arc.

[0039] Also, according to the present invention the cutting of the round or flat wire and the shaping of the wire ends is performed on two separated hydraulic presses unlike before that both operations were performed at the same time on a single press (4). This method ensures better tool wear and better product quality. 

1. Method for the manufacture of metallic frames for inner spring mattresses of round wire or flat wire of any cross section and material subject to plastic bending, which consists of the following stages: straightening, production of an open frame of a length equal to the circumference of the frame under production, cut-off of the round wire or flat wire with the formation of suitable incisions at the ends of the said round wire or flat wire simultaneously with the cut-off or prior or following it, production of suitable elliptical or circle, connection of the two ends with a connective plate or a small tube or by welding or with glue and a suitable connective plate or a small tube and finally bending of the angles of the frame.
 2. Method according to claim 1 which is characterized by that the shaping of the round wire or flat wire in an open frame of a suitable elliptical or circular shape, connection of the two ends of the said open frame are performed prior to bending.
 3. Method according to claim 1 , which is characterized by that it requires a suitable shaping of the ends of the open frame during the cut-off or prior to or following it and the suitable pressure of the suitable connection plate or of the small tube so that the material of the said connective plate or of the small tube penetrates into the suitable incisions resulting in a strong connection of the ends of the frame.
 4. Method for the manufacture of metallic frames for inner spring mattresses according to claim 1 , which necessitates the suitable shaping of the two ends of the frame during the cut-off or before or following it so that they can hook together and then be wound suitably with a suitable plate or a small tube, resulting in a strong connection of the ends of the frame.
 5. Method for the manufacture of metallic frames for inner spring mattresses according to claim 1 , which necessitates the welding of the two ends of the frame, resulting in their strong connection together.
 6. Method for the manufacture of metallic frames for inner spring mattresses according to claim 1 , which necessitates the connection of the two ends of the frame with suitable glue and suitable plate or small tube, resulting in a strong connection of the ends of the frame.
 7. Method for the manufacture of metallic frames for inner spring mattresses according to claim 1 , made of round wire or flat wire which necessitates the shaping of the open frame into an elliptical or circular shape, connection of the two ends with a suitable means of connection and then bending.
 8. Method for the manufacture of metallic frames for inner spring mattresses according to claim 1 of round wire which necessitates the shaping of the open frame into an elliptical or circular shape along the side with the smallest inertia torque of the flat wire, connection of the two ends with a suitable means of connection and then bending at right angles to the plane of the elliptical or circle.
 9. Machine for the manufacture of metallic frames made of round wire or flat wire (1) which is characterized by the feeding and straightening (2) mechanism of the round wire or flat wire (), the length measuring instrument (3) of the fed round wire or flat wire (1), the length measuring instrument (3) of the fed round wire or flat wire (1), the cutter (4) which cuts and at the same time shapes the ends of the round wire or flat wire suitably (1), a guide (5) which consists of two parts, one fixed and one moving freely around a pin (17), a rotation mechanism (8) with a jaw (7) for the production of the suitable open elliptical or circular frame, a connective mechanism (6) fed by a connective plate or a small tube (14), an arm (13) for the transportation of the closed frame from the connective mechanism (6) to the suitably arranged bending unit (9), where such bending unit is capable of feeding and bending the closed elliptical or circular frame.
 10. Machine for the manufacture of metallic frames made of round wire or flat wire (1) as referred to in claim 9 which is characterized by the feeding and straightening mechanism (2) of the round wire or the flat wire (1), the cutter (4) which cuts and at the same time suitably shapes the ends of the round wire or flat wire (1), a guide (5) which consists of two parts, one fixed and one moving freely around a pin (17), a rotation mechanism (8) with a jaw (7) for the production of the suitable open elliptical or circular frame, the connective mechanism (6) fed by the connective plate of a small tube (14), the arm (13) for the transportation of the closed frame by the connective mechanism (6) to the suitably shaped bending unit (9), which bending unit is capable of feeding and bending the closed elliptical or circular frame, where such mechanisms are controlled and guided by a microprocessor.
 11. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 which is characterized by that it features an arm (13) for the transportation of the closed elliptical or circular frame to the suitably arranged bending unit (9).
 12. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 which is characterized by that it features a bending unit (9), which is capable of feeding and bending the elliptical or circular closed frame at predetermined points and at predetermined angles so that the frame for inner spring mattresses is produced at the desirable dimensions and shape, where such bending unit is suitably arranged.
 13. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 , which is characterized by that it features cutter (4) which is capable of cutting and at the same time suitably shaping the ends of the round wire or flat wire (1) creating suitable incisions to them.
 14. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 , which is characterized by that it features a guide (5) which consists of two parts, one fixed and one moving freely around a pin (17) via which the round wire or flat wire is driven (1).
 15. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 , which is characterized by that it features a connective mechanism (6) which may intersect with the suitable connective plate or small tube (14), to wind it and to grasp it around the two ends of the frame under construction and finally to press the connective plate or small tube (14) so that the material of the connective plate or small tube penetrates into the suitable incisions at the two ends of the frame under construction shaped by the cutter (4).
 16. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 , which is characterized by that it features an arm (8) with a jaw (7), which is capable of moving along a circular or other suitable curved track, thus shaping the round wire or flat wire (1) of the frame suitably.
 17. Machine for the manufacture of metallic frames for inner spring mattresses according to claim 9 , which is characterized by that it features a connective mechanism (6) with two jaws (22,23) suitably arranged so that they may retain the two ends of the round wire or flat wire (1) of the frame under construction at a suitable position on the connective mechanism (6). 